Contents

Summary

Did you know?

Before 1990 this species was not known from New York State but in September of that year two populations were discovered within one day of each other at two different places by two different botanists. One population was discovered on Fishers Island in Long Island Sound and one near Orient Point on the North Fork of Long Island.

State Ranking Justification

There are three existing populations in New York, but this species has only been known in the state since 1990. One population is small with fewer than 50 plants and population numbers are unknown but probably fairly small for the other two populations since the marshes they are in are small.

Short-term Trends

All three existing populations have not been resurveyed so short-term trends are unknown.

Long-term Trends

This species was only discovered in New York in 1990 so long-term trends are unknown.

Conservation and Management

Threats

One site has development nearby and may be affected by the increase in human disturbance. Threats are unknown in the remaining populations.

Conservation Strategies and Management Practices

Control Phragmites invasions in the salt marshes where it exists and prevent new incursions. Natural buffers should be established around the salt marshes to decrease pollution runoff and other direct human disturbances.

Research Needs

Research is needed to understand what is limiting both population numbers and size on Long Island.

Habitat

Habitat

In New York Seaside Orach has only been collected from the upper edges of rocky beaches (New York Natural Heritage Program 2010). Saline or brackish marshes and saline coastal strands (FNA 2003). Sea beaches (Gleason and Cronquist 1991).

Associated Ecological Communities

Marine intertidal gravel/sand beach

Associated Species

Artemisia campestris

Atriplex patula (spear orach)

Chenopodium

Erechtites hieraciifolia

Fallopia scandens (climbing false buckwheat)

Lathyrus japonicus

Oenothera

Xanthium strumarium

Range

New York State Distribution

This herb is only known from Fishers Island in Suffolk County where it was discovered in 1992.

Global Distribution

This saltmarsh plant is most common in northeastern Canada but ranges south to New York and west to Manitoba and Nebraska. It is considered introduced in Illinois and Kentucky.

Best Places to See

No populations are known from locations accessible to the public

Identification Comments

General Description

Seaside Orach is an herbaceous annual plant with often prostrate stems up to 1 meter long. The leaves are opposite or nearly so, triangular or arrow-shaped, sometimes with two opposite lobes near the base, and a few large teeth. The infloresence is terminal, with leaves or bracts throughout. The female flowers lack petals or sepals, and are enclosed by two triangular leafy bracteoles, these 5 to 13 millimeters long and joined together from the base to near the middle. The seeds are dimorphic: either brown and 2.5 to 4 mm wide, or less commonly, black and 1.5 to 2.5 mm wide (Gleason and Cronquist 1991).

Best Life Stage for Proper Identification

Seaside Orach is most easily identified when in fruit.

Similar Species

Unlike Atriplex glabriuscula, Atriplex hastata does not have leaves or bracts throughout the inflorescence. Atriplex laciniata has hard bracteoles enclosing the seeds and similarly shaped but scurfy leaves. In contrast, Atriplex glabriuscula has spongy herbaceous bracteoles and smooth leaves. (Gleason and Cronquist 1991).Save file

Best Time to See

Seaside Orach is an annual species, flowering in late summer and persisting into November.

Flowering

Fruiting

The time of year you would expect to find Seaside Orach flowering and fruiting in New York.

Other References

Gleason, Henry A. and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York. 910 pp.

Holmgren, Noel. 1998. The Illustrated Companion to Gleason and Cronquist's Manual. Illustrations of the Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York.

Mitchell, Richard S. 1986. A checklist of New York State plants. Bulletin No. 458. New York State Museum. 272 pp.

Mitchell, Richard S. and Gordon C. Tucker. 1997. Revised Checklist of New York State Plants. Contributions to a Flora of New York State. Checklist IV. Bulletin No. 490. New York State Museum. Albany, NY. 400 pp.

New York Natural Heritage Program. 2019. New York Natural Heritage Program Databases. Albany, NY.